The research, published in the Annals of Internal Medicine, analyzed patient satisfaction scores, lengths of stay and rates of mortality and 30-day readmissions for common conditions at 803 hospitals that adopted a physician-employment model.

When researchers compared these measures to those of 2,085 hospitals that didn’t operate under that model, they found no correlation between changing models and improved outcomes. The only measure showing significant improvement under the employment model was readmissions for pneumonia.

"Our study, which used contemporary national data, suggests that a fundamental improvement in care delivery will require more than mere changes in hospital-physician integration, and if physician employment is a key ingredient, it must be linked to other key goals, such as hospital prioritization of quality, to be successful," they wrote.

While the research will likely surprise healthcare leaders who have made large investments in the model, it makes sense in the context of the doctor-patient relationship, according to Richard Gunderman, M.D., Ph.D., of Indiana University, who wasn't involved in the study.

When employed by hospitals, physicians lose autonomy and don’t have final say over individual patient care, he toldMedscape Medical News,

Meanwhile, larger organizations with their own standards blame or penalize doctors for spending what they assess to be too much time with a patient, which can hurt morale among doctors and contribute to burnout. In the future, he predicted, "we will learn that if healthcare organizations are going to be very big, they need to devise new means of thinking and acting as though they're smaller.”